Various types of methods such as wireless communication have been proposed for exchanging information. As one of the methods, there is proposed human body communication by an electrostatic field or an induction field induced around a human body (Patent Document 1). In addition, there is introduced a method of using human body communication for data transmission and reception between external terminals such as mobile phones and portable game machines, in which, for example, data transmission and reception is performed from an external terminal of a person to another external terminal of another person via human bodies when they shake hands (Patent Document 2). On the other hand, an electronic business card device which can exchange business cards by an electromagnetic wave without using paper is also proposed (Patent Document 3).    Patent Document 1: JP-A-2006-271798    Patent Document 2: JP-A-2006-81025    Patent Document 3: JP-A-2007-272310